1. Field of the Invention
The present invention relates to medical devices with polymeric coatings and more particularly to medical devices having polymer coatings that release therapeutic agent.
2. Brief Description of the Background Art
Local delivery of therapeutic agents is an important adjunct to mechanical treatment of diseases. For example, local delivery of restenosis-inhibiting therapeutic agents has been proposed in connection with the insertion of a coronary stent after percutaneous transluminal coronary angioplasty, as the presence of the stent can exacerbate neointimal hyperplasia, which is believed to be a significant causative factor in the restenosis of the vessel.
One common method of local therapeutic agent delivery is to allow the therapeutic agent to diffuse from a polymer matrix. In this connection, controlling release is an important aspect in providing effective therapy. Furthermore, controlling the manufacture of the polymer matrix is an important factor in determining the ultimate release rate.